Driver should be fine w/ this build of DSS V6 and your firmware, I would check the RAID Controllers health, maybe re-apply the firmware, I have seen errors like this from 3Ware cards and after several reboots the effects pop up. I would also download the 3Ware logs and get them to the 3Ware guys as well to verify if this can lead to any ECC or chip errors.
I have also seen where if the card is to hot weird errors can happen.